Method and system for analyzing physical conditions using digital images

ABSTRACT

Systems and methods are provided for analyzing conditions associated with a physical feature using digital images. The method comprises acquiring a white-light image and an ultraviolet (“UV”) image of at least a portion of a body surface, such as a person&#39;s face, each of the white-light and UV images including a plurality of pixels and each pixel in the UV image corresponding to a respective pixel in the white-light image. The method further comprises identifying feature pixels in the white-light and UV images, and obtaining results associated with at least one physical condition using information in the feature pixels in the first white light and UV images.

FIELD OF THE INVENTION

The present invention relates generally to digital image acquisition,processing and analysis, and more particularly to analyzing physicalconditions of people using digital images.

BACKGROUND INFORMATION

The human body is sensitive to a variety of conditions and changes thatmay require long-term monitoring and care. For instance, skin conditionssuch as acne, wrinkles, UV damage, and moles are common in a largenumber of people. Most of these conditions benefit from the use of oneor more skin care products, often designed to target a specificcondition. The lips likewise serve important physiological as well associological functions. One can express emotion during verbal andpsychological communication using movements of lips. Lips are alsohighly sensitive areas for both tactile and thermal stimuli. Othernotable characteristics of the lips are their lower barrier andwater-holding functions with respect to facial skin, the significantlygreater skin blood flow on the lip with respect to that on the cheek,and the significantly higher surface temperature on the lip with respectto that on the cheek. In spite of the above, lip aging process is notwell understood and it has seldom been quantitatively investigated. Inparticular, limited research has been done to investigate the effect ofaging on lip wrinkling, color (rosiness) and surface area.

There are a variety of skin care products available today which are soldor administered to customers or patients. The products rely mainly onqualitative and highly subjective analysis of facial features and skindefects or ailments associated with the customers or patients. Effectsof the skin care products may also be tested at a qualitative level,without a quantitative and objective proof of effectiveness. Visits todermatologist offices and medical spas offering skin care products andtreatment tend to be limited to a visual analysis of the patients' skinconducted by a doctor or other specialist, with rare instances of use ofdigital image processing technology to aid in the course of treatment.There are also no products available today that let patients evaluatetheir skin conditions while on the road, for example, at a beach whilebeing exposed to UV radiation.

With the recent advancements in digital imaging and microprocessortechnology, the medical and healthcare industry are starting to finddigital image processing and analysis helpful in the study, detection ordiagnosis of defects or diseases on the surface of or inside the humanbody or other living organisms. Although several research projects havebeen carried out in the skin care industry to explore computer analysisof skin images, the technology of using digital images of a person'sskin to evaluate a variety of skin conditions associated with the personis still primitive and in need of substantial development. Quantitativeanalysis of physical features, e.g. the skin, lips, hair, will helptremendously in the development of effective dermatological agents, suchas those designed to target aging.

There is therefore a need for a method and system capable of analyzing avariety of conditions associated with a physical feature, e.g. skin,lip, hair, teeth, with the use of digital images.

There is also a need for a method and system for analyzing a variety ofconditions associated with a physical feature, e.g. skin, lip, hair,teeth, with the use of portable devices equipped to acquire digitalimages of a person's skin.

SUMMARY OF THE INVENTION

In one aspect of the invention, a white-light image and an ultraviolet(UV) image of a person's physical feature are acquired with an imageacquisition device. Each of the white-light and UV images include aplurality of pixels and each pixel in the UV image corresponds to arespective pixel in the white-light image. The white-light and UV imagesmay be acquired by applying UV light to the physical feature of thesubject and applying white light to the physical feature of the subject.In some embodiments, a light-absorbing cloak is used to cover part ofthe subject before acquiring the UV image. The white-light and UV imagesmay be captured by a portable device and transmitted or transferred to acomputing device for analysis or, alternatively, the capture andanalysis may be carried out by one device unit.

In accordance with the present invention, the white-light and UV imagesare analyzed to identify feature pixels. Information in the featurepixels is used to identify or characterize at least one conditionassociated with the physical feature. The lip conditions that may becharacterized include, without limitation, lip surface area, color, finelines, wrinkles, and characteristics associated with lip edgedemarcation. Characteristics associated with lip edge demarcation mayinclude, e.g. color contrast, line roughness, color variation, etc. Skinconditions that may be detected and classified include, but are notlimited to, skin tone, UV damage, pores, wrinkles, hydration levels,elasticity, collagen content, skin type, topical inflammation or recentablation, keratosis, deeper inflammation, sun spots, different kinds ofpigmentation including freckles, moles, growths, scars, acne, fungi,erythema and other artifacts. Information in the skin pixels may also beused to perform feature measurements such as the size and/or dimensions,e.g. length or volume, of an eyelash, lip, nose, eyes, ears, chins,cheeks, forehead, eyebrows, pore, among other features.

Also provided by the present invention is a computer readable mediumstoring therein program instructions that, when executed by a processor,cause the processor to perform a method for analyzing physicalconditions associated with a subject. The program instructions mayinclude: instructions for acquiring a first white-light image and afirst UV image of the subject, each pixel in the first UV imagecorresponding to a respective pixel in the first white-light image;instructions for identifying, on a pixel by pixel basis, feature pixelsin the first white-light and UV images; and instructions for obtainingresults associated with at least one condition associated with aphysical feature using information in the feature pixels in the firstwhite light and UV images.

In another aspect of the invention, a computer system including theabove-described computer readable medium is provided. Also provided is asystem for analyzing conditions associated with a physical feature ofthe subject. The system may include an image acquisition deviceconfigured to acquire a white-light image and a UV image of the subjectand a computer system configured to identify, on a pixel by pixel basis,feature pixels in the first white-light and UV images, and to obtainresults associated with at least one condition associated with thefeature using information in the feature pixels in the first white lightand UV images. Each of the white-light and UV images has a plurality ofpixels and each pixel in the UV image corresponding to a respectivepixel in the white-light image.

The image acquisition device may have a sensor rotatable to adjust anaspect ratio of the white-light or UV image according to control signalsfrom the computer system. In other embodiments of the invention, theimage acquisition device includes a sensor; an optical assembly with alens and configured to form images of the subject on the sensor; and aplurality of light sources, at least one of which is an LED lightsource, attached in proximity to the lens of the optical assembly. Insome embodiments, a plurality of LED light sources is disposedconcentrically about the lens. In other embodiments, the opticalassembly also includes a zoom lens and a system for controlling same. Atleast a portion of the light sources have UV transmission filters builtin or installed thereon, and at least a portion of the light sourceshave infrared absorption filters built in or installed thereon.

In view of the foregoing, the present invention provides systems andmethods for analyzing lip conditions using digital images. These andother objects, advantages, and features of the invention will becomeapparent to those persons skilled in the art upon reading the details ofthe invention as more fully described below.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other objectives, advantages and features of theinvention will become apparent upon reading the following detaileddescription and referring to the accompanying drawings in which likenumbers refer to like parts throughout and in which:

FIG. 1 is a simplified block diagram of a system for analyzing skinconditions according to embodiments of the present invention;

FIG. 2A is a line drawing of an exemplary image acquisition device inthe system shown in FIG. 1 according to an exemplary embodiment of thepresent invention;

FIG. 2B is a line drawing showing an aspect ratio of a sensor in theexemplary image acquisition device of FIG. 2A being adjusted toaccommodate the dimensions of a portion of a person's body surface to beimaged;

FIG. 2C is a schematic of exemplary image acquisition devices that canbe converted into the image acquisition device shown in FIG. 2A;

FIG. 2D is a schematic of an exemplary embodiment of the presentinvention showing an acquisition device coupled to a computing devicevia a network;

FIG. 3A is a line drawing of a flash light source in the system shown inFIG. 1 according to an exemplary embodiment of the present invention;

FIG. 3B is a chart illustrating a transmission spectrum of a UV bandpassfilter as compared with transmission spectra of other white-lightfilters;

FIG. 4 is a line drawing of an exemplary setup for the systemillustrated in FIG. 1 according to an exemplary embodiment of thepresent invention;

FIG. 5 is a simplified block diagram of a computing device in the systemillustrated in FIG. 1 according to an exemplary embodiment of thepresent invention;

FIG. 6 is a line drawing of a user interface associated with thecomputing device illustrated in FIG. 1 according to an exemplaryembodiment of the present invention;

FIG. 7A is a flowchart illustrating a method for analyzing skinconditions using digital images according to an exemplary embodiment ofthe present invention;

FIG. 7B is a line drawing illustrating the alignment of a subject's faceperformed prior to acquiring current results and comparing them withprevious results at step 740 of the flowchart of FIG. 7A;

FIG. 8A is a flowchart illustrating process steps for acquiring digitalimages of a body surface according to an exemplary embodiment of thepresent invention;

FIG. 8B is a line drawing of a person in front of an image acquisitiondevice wearing a cloak according to an exemplary embodiment of thepresent invention;

FIG. 9A is a flowchart illustrating process steps for identifying skinpixels in the digital images according to an exemplary embodiment of thepresent invention;

FIG. 9B is a table listing exemplary ranges of pixels values fordifferent color channels for each of a plurality of color spaces thatare used to identify skin pixels;

FIGS. 10( a) to 10(e) are simplified block diagrams illustrating amethod for generating a skin mask according to an exemplary embodimentof the present invention;

FIG. 11 is a flowchart illustrating process steps for obtaining UVdamage results from the digital images according to an exemplaryembodiment of the present invention;

FIG. 12 is a flowchart illustrating process steps for obtaining skintone results from the digital images according to an exemplaryembodiment of the present invention;

FIG. 13A is a flowchart illustrating process steps for obtaining resultsrelated to certain skin conditions according to an exemplary embodimentof the present invention;

FIG. 13B is a table listing exemplary pixel colors and intensitiesassociated with different skin conditions;

FIG. 14 is a flowchart illustrating process steps for obtaining resultsrelated to wrinkles according to an exemplary embodiment of the presentinvention;

FIG. 15A is a flowchart illustrating process steps for displayingresults of skin conditions according to an exemplary embodiment of thepresent invention;

FIG. 15B is a line drawing of a user interface for displaying a timelineof results of skin conditions according to an exemplary embodiment ofthe present invention; and

FIG. 15C is a line drawing of a user interface for displaying resultsrelated to a selected skin condition as compared with previous resultsrelated to the same skin condition.

FIG. 16 is a photograph of an exemplary system showing the white lightsource in operation according to an exemplary embodiment of the presentinvention.

FIG. 17 is another photograph of an exemplary system with a computingdevice and a display according to an exemplary embodiment of the presentinvention.

FIG. 18 is a side perspective view of an exemplary system according toan exemplary embodiment of the present invention.

FIG. 19 is a frontal close-up view of an exemplary system according toan exemplary embodiment of the present invention.

FIG. 20 is an illustration of an exemplary system as it would appear ona tabletop setup according to an exemplary embodiment of the presentinvention.

FIG. 21 is an illustration of another exemplary system as it wouldappear on a tabletop setup according to an exemplary embodiment of thepresent invention.

FIGS. 22A-22C are line drawings of an exemplary source light shield (seeFIG. 22A), a side cross-sectional view of an exemplary image acquisitionsystem (see FIG. 22B), and a rear view of an exemplary housing backpanel (see FIG. 22C), respectively, according to an exemplary embodimentof the present invention.

FIG. 23 shows the spectral intensity curve for a 365 nm UV LED lightsource.

FIGS. 24A-24B are comparison photos of the same subject illustrating thebroad spectrum noise reduction achievable with the use of UV LED asopposed to a flash light source according to an exemplary embodiment ofthe present invention.

FIG. 25 is a table showing the optical performance, as measured by fullwidth half maximum, of select LED light sources at various wavelengths.

FIG. 26 is an image of a subject captured using a system with abroadband circular polarizer according to an exemplary embodiment of thepresent invention.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

Before the present invention is described, it is to be understood thatthis invention is not limited to particular embodiments described, assuch may, of course, vary. It is also to be understood that theterminology used herein is for the purpose of describing particularembodiments only, and is not intended to be limiting, since the scope ofthe present invention will be limited only by the appended claims.

Where a range of values is provided, it is understood that eachintervening value, to the tenth of the unit of the lower limit unlessthe context clearly dictates otherwise, between the upper and lowerlimits of that range is also specifically disclosed. Each smaller rangebetween any stated value or intervening value in a stated range and anyother stated or intervening value in that stated range is encompassedwithin the invention. The upper and lower limits of these smaller rangesmay independently be included or excluded in the range, and each rangewhere either, neither or both limits are included in the smaller rangesis also encompassed within the invention, subject to any specificallyexcluded limit in the stated range. Where the stated range includes oneor both of the limits, ranges excluding either or both of those includedlimits are also included in the invention.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. Although any methods andmaterials similar or equivalent to those described herein can be used inthe practice or testing of the present invention, some potential andpreferred methods and materials are now described. All publicationsmentioned herein are incorporated herein by reference to disclose anddescribe the methods and/or materials in connection with which thepublications are cited. It is understood that the present disclosuresupersedes any disclosure of an incorporated publication to the extentthere is a contradiction.

It must be noted that as used herein and in the appended claims, thesingular forms “a”, “an”, and “the” include plural referents unless thecontext clearly dictates otherwise. Thus, for example, reference to “acell” includes a plurality of such cells and reference to “the vector”includes reference to one or more vectors and equivalents thereof knownto those skilled in the art, and so forth.

The term “subject,” as used herein, refers to any human or animal.

In an exemplary application of the method of the present invention, awhite-light image and an ultraviolet (“UV”) image of the skin of aperson's face, are acquired each of the white-light and UV imagesincluding a plurality of pixels, are acquired with an image acquisitiondevice.

The image acquisition device may include, but is not limited to,film-based or digital cameras, wireless phones and other personaldigital appliances (“PDAs”) equipped with a camera, desktop and notebookcomputers equipped with cameras, and digital music players, set-topboxes, video game and entertainment units, and any other portable devicecapable of acquiring digital images and having or interacting with atleast one white-light and UV light sources.

In accordance with the present invention, the white-light and UV imagesare analyzed to identify feature pixels therein. In the example providedabove, the feature pixels would be skin pixels. Information in the skinpixels is used to identify at least one skin condition. Conditionsassociated with the skin that may be detected and classified include,but are not limited to, skin tone, pigment evenness, pigment darkness,diffuse redness, e.g. indicative of sensitive or reactive skin, intenselocalized red levels, e.g. indicative of vascularlesions/telangiectasias, radiance intensity, enlarged pores, roughnessvariation, emerging lines, fine lines, wrinkles, UV damage, pore health,hydration levels, collagen content, skin type, topical inflammation orrecent ablation, keratosis, deeper inflammation, sun spots, differentkinds of pigmentation including freckles, moles, growths, undereyecircles, scars, acne, fungi, erythema and other artifacts. Informationin the feature pixels may also be used to perform feature measurementssuch as the size, volume of a lip, nose, eyes, ears, chins, cheeks,forehead, eyebrows, teeth, among other features. Even a pore size orspot count measurement as well as the length, thickness and/or curvatureof an eyelash, can be made based on information from the feature pixels.

In one exemplary embodiment, the skin pixels are identified by examiningeach pixel in the white-light and/or UV images to determine if the pixelhas properties that satisfy predetermined criteria for skin pixels.Examination of the pixels in the white-light and UV images may includeexamining with reference to a skin map or skin mask, which, as generallyused herein, is a virtual image, matrix or data group having a pluralityof elements, each element corresponding to a pixel in the white-light orUV image.

In one exemplary embodiment, the white-light image is of a first colorspace, and at least one other white-light image is constructed byconverting the original white-light image into at least one second colorspace. For each element in the skin mask, the corresponding pixel ineach of the white-light images is examined with reference topredetermined criteria associated with a respective color space. A firstvalue is assigned to an element in the skin mask if the correspondingpixel in each of the white-light images has pixel values that satisfypredetermined criteria for skin pixels associated with a respectivecolor space, and a second value is assigned to an element in the skinmask if the corresponding pixel in any of the white-light images haspixel values that do not satisfy predetermined criteria for skin pixelsassociated with a respective color space. In a further exemplaryembodiment, some of the elements in the skin mask are predefined ascorresponding to non-skin features according to a coordinate reference.These elements are assigned the second value disregarding what valuestheir corresponding pixels in the white-light images have.

After all elements of the skin mask have been assigned the first orsecond value, each pixel in any of the white-light and UV images thatcorresponds to an element having the first value in the skin mask wouldbe identified as a skin pixel, and each pixel in any of the white-lightand UV images that corresponds to an element having the second value inthe skin mask would be identified as a non-skin pixel. Pixels that areidentified as non-skin pixels are not considered in obtaining resultsfor the at least one skin conditions.

In one aspect of the invention, each skin pixel of the white-light andUV images includes values associated with three color channels, andresults obtained for UV damage are computed based on values associatedwith one of the three color channels in the skin pixels of the first UVimage.

In another aspect, a standard deviation is computed using valuesassociated each of the three color channels in the skin pixels of thewhite-light image, and the standard deviations for the three colorchannels, or their average value, is used as a quantitative measure forthe skin tone of the skin under analysis.

In a further aspect of the present invention, a color value and anintensity value associated with each of the skin pixels in the UV imageare computed and examined with reference to at least one look-up tableto determine if they correspond to a specified skin condition. For eachskin pixel in the UV image that is determined to correspond to aspecified skin condition, surrounding skin pixels are examined for thespecified skin condition to determine a size of a skin area having thespecified skin condition. Statistical results such as a number and/ordistribution of the areas having one or more specified skin conditionscan also be provided.

In one exemplary embodiment, the results associated with at least oneselected skin condition can be displayed on a user interface using animage having the at least one type of skin condition highlighted, and/orwith at least one number or chart quantifying the skin condition. In afurther exemplary embodiment, both current and prior results associatedwith at least one selected skin condition for the person are displayednext to each other for comparison. The results compared may includestatistical results or other data analysis quantifying the skinconditions that are identified and classified for the subject.

In this exemplary embodiment, an alignment of the subject's portion of abody surface being analyzed, such as the subject's face, is performedprior to the comparison. The alignment ensures that images acquired forgenerating the current results are aligned with the images acquired forgenerating the previous results for the same subject. A grid is used toalign portions of the body surface of the subject being analyzed, suchas the subject's nose, eyes, and mouth, with the same portions displayedon previous images acquired for generating previous results for the samesubject. In this manner, the present invention has the advantage ofproviding repeatable facial images and tracking the progression andchanges over time in the condition being studied.

According to these and other exemplary embodiments of the presentinvention, the system for analyzing conditions associated with physicalfeatures in a subject generally includes an image acquisition device, atleast one light source coupled to the image acquisition device, and acomputing device coupled to the image acquisition device and to thelight source, and a display coupled to the computing device. Thecomputing device includes modules for carrying out different aspects ofthe method for analyzing skin conditions as summarized above anddescribed in more detail below. The modules may be in hardware orsoftware or combinations of hardware and software. In one exemplaryembodiment, the computing device includes a microprocessor and a memorydevice coupled to the microprocessor, and the modules include softwareprograms stored as program instructions in a computer readable mediumassociated with the memory device.

In one exemplary embodiment, the image acquisition device coupled withat least one light source may be connected to the computing device via awired or wireless network. Accordingly, images acquired by the imageacquisition device coupled with at least one light source may be sent tothe computing device via a network for analysis. The results of theanalysis may then be sent to a user of the image acquisition device viaa number of communication means, including, but not limited to, email,fax, voice mail, and surface mail, among others. Alternatively, theresults may be posted on a web site or another medium for laterretrieval by the user.

In another exemplary embodiment, the image acquisition device coupledwith at least one light source may include a portion or all of themodules for carrying out different aspects of the invention assummarized above and described in more detail herein below. In thisexemplary embodiment, the images acquired by the image acquisitiondevice may be analyzed on the device itself, thereby eliminating theneed for the images to be sent to a separate computing device connectedto the image acquisition device. Alternatively, a partial analysis maybe performed in the image acquisition device and the images may still besent to a separate computing device for further analysis.

The image acquisition device and the systems of the present inventionmay be used at a number of locations, including doctor officers, medicalspas and other health care facilities, open spaces such as parks andbeaches, inside transportation vehicles such as cars and airplanes or atany other location where it is desired to acquire information aboutone's skin.

Advantageously, the present invention enables doctors and other skincare specialists to obtain quantitative measures of a variety of skinconditions. The quantitative measures may be acquired before or after askin care treatment to evaluate the suitability of the treatment for agiven condition. In addition, the present invention enables patients toobtain rapid assessments of their skin at any location, therebyassisting them in the proper care and maintenance of their skin on adaily basis.

Generally, in accordance with exemplary embodiments of the presentinvention, systems and methods are provided for identifying andanalyzing skin conditions in a person based on digital images of aportion of the person's body. Lip conditions and/or characteristics thatmay be identified and analyzed by the systems and methods of the presentinvention include, but are not limited to, surface area, color, finelines, wrinkles, color contrast, line roughness, color variation,collagen content, topical inflammation or recent ablation, keratosis,deeper inflammation, sun spots, different kinds of pigmentationincluding freckles, moles, growths, scars, erythema and other artifacts.

FIG. 1 depicts a simplified block diagram of a system 100 for analyzingskin conditions according to an exemplary embodiment of the presentinvention. As shown in FIG. 1, system 100 includes image acquisitiondevice 110, at least one light source 120 coupled to image acquisitiondevice 110, computing device 130 coupled to image acquisition device 110and to at least one light source 120 either directly or through imageacquisition device 110, display 140 coupled to computing device 130, andoptionally printer 150 also coupled to computing device 130. System 100is configured to acquire digital images of subject 101, such as aperson's face, and to process the digital images to obtain resultsrelated to at least one physical condition associated with the person.

In one exemplary embodiment, as shown in FIG. 2A, image acquisitiondevice 110 is part of acquisition device 200 having image sensor 114 andoptical assembly 112 in front of image sensor 114 and configured to forman image of subject 101 on image sensor 114. Image sensor 114 mayinclude, for example, 5-15 or more million Mega pixels made of photondetecting devices, such as charge-coupled devices (“CCD”), CMOS devicesor charge-injection devices (“CID”), among others. Each pixel includesthree sub-pixels corresponding to three different color channels.

The number of pixels used in image sensor 114 to capture the white-lightand UV images can be varied or held fixed. In some embodiments, 12 megapixel resolution images are captured. As shown in FIG. 2B, image sensor114 is rotated to have its aspect ratio changed from 1.5:1 (36:24) to1:1.5 (24:36) in order to capture the whole length of a person's faceand to more accurately match a facial ratio of 1:1.61. In a furtherexemplary embodiment, image sensor 114 may have a variable number ofpixels.

FIG. 2A also shows a plurality of light sources 120 as parts ofacquisition device 200, including, for example, two flash light sources120 on two sides of acquisition device 200, flash light source 120 ontop of acquisition device 200, and optionally another flash light source120 at the bottom of acquisition device 200. Having more than one flashlight sources 120 allows more uniform exposure of subject 101 to lightduring imaging.

Other types of light sources are also contemplated by the presentinvention. For instance, the use of LED light sources to illuminate thefeature being imaged provides some unique advantages; LED light sourcesare more compact, economical, and energy efficient as compared to flashlight sources. Furthermore, the use of LED light sources with thepresent invention allows for more precise calibration and control overthe illumination of the feature being studied. In particular, asillustrated by FIGS. 24A-24B, a UV LED light source provides images withmuch richer detail and even information on what lies beneath the skin'ssurface. Operation and exemplary configurations of the light sources inthe present invention are shown in FIG. 16, FIG. 18, FIG. 19, and FIG.22B. The use of different types of light sources is contemplated by thepresent invention and may be preferred in some instances, as would beappreciated by one of ordinary skill in the art. For instance, in someembodiments, at least one LED light source is used. In otherembodiments, the light sources may comprise at least two LED lightsources of distinct emission wavelengths, e.g. in the visible or UVspectra. In still other embodiments, three or eight LED light sourcesare employed. See FIG. 19 for an exemplary eight-LED ring configuration.

Referring to FIG. 16, which shows a frontal view of the imageacquisition system with its white light source in operation, someembodiments may comprise a frusto-conical source light shield 1620extending outwardly from the lens of the optical assembly. As shown, thewhite light is directed towards the subject through the source lightshield 1620. The image acquisition device may further include an ambientlight shield 1630 positioned at least partially over the distal end ofthe frusto-conical source light shield 1620, shown in FIG. 17-22A. Theambient light shield 1630 may be formed of an opaque material to reducenoise from illumination external to the system. In some embodiments, theambient light shield 1630 may have a reflective interior surface topromote uniform illumination on the subject.

Referring to FIG. 18, the image acquisition device 200 may furthercomprise a housing 1640 having a chamber sized and configured to enclosethe white light source 120 a. In some embodiments, the housing 1640 maycomprise a detachable panel as illustrated by component 1640 a in FIG.22C. The white light source 120 a may adopt any configuration known inthe art. In some embodiments, the white light source 120 a has aring-shaped configuration and is positioned behind the source lightshield 1620. The source light shield 1620 may be formed of a lightdiffusing material so as to permit the light to travel towards thesubject being imaged.

As appreciated by those of skill in the art in view of the presentdisclosure, different light sources may be configured to emit differentcolors or wavelengths of light, but the number of light sources 120 andtheir positions in system 100 can be varied without affecting thegeneral performance of the system. In some embodiments of the presentinvention, the UV light source is an LED type with an emissionwavelength of about 365 nm. Exposure of skin to 365 nm UV light sourcepresents low risks and induces autofluorescence in the visible range,which is readily detectable with a conventional camera. In one exemplaryembodiment, a portion of light sources 120 may be configured toilluminate subject 101 with white light, and another portion of lightsources 120 may be configured to emit ultraviolet (“UV”) light. Otherlight sources, such as the sun and surrounding lights may also be usedwithout deviating from the principles and scope of the presentinvention.

Acquisition device 200 may also include other parts or components thatare not shown, such as a shutter, electronics for allowing computingdevice 130 to control the shutter, flashings from light sources 120, andelectronics for outputting captured images to computing device 130 foranalysis, among others. To prevent saturation of the pixels in imagesensor 114, acquisition device 200 may also include anti-bloomingdevices. At a minimum, acquisition device 200 may include imageacquisition device 110 and at least one light source 120. Acquisitiondevice 200 may further include a zoom lens and a zoom lens controlsystem, as can be procured commercially. Advantageously, use of the zoomlens provides images with much higher spatial resolution to enable, e.g.accurate measurement of pore size, hair strands, hair follicles, spots,and moles. In some embodiments, the acquisition device 200 includes abroadband circular polarizer (not shown) that is commercially available.The effects of using such a circular polarizer is illustrated in FIG.26, which demonstrates reduction of glare from the skin and provides amuch clearer image.

Acquisition device 200, as shown in FIG. 2C, may be converted from anumber of portable image acquisition devices 110, including, but notlimited to, film-based camera 205 or digital camera 210, wireless phone215 and other personal digital appliances (“PDAs”) equipped with acamera such as PDA 220, desktop computer 225 and notebook computer 230equipped with cameras, and digital music player 235, set-top boxes,video game and entertainment units 240, and any other device capable ofacquiring digital images and having or interacting with at least onelight source, such as light sources 120 on the top, bottom, and on thesides of image acquisition device 110.

In one exemplary embodiment, shown in FIG. 2D, acquisition device 200may be connected to computing device 130 via wired or wireless network245. Accordingly, images acquired by acquisition device 200 are sent tocomputing device 130 via network 245 for analysis. The results of theanalysis may then be sent to a user of acquisition device 200 via anumber of communication means, including, but not limited to, email,fax, voice mail, and surface mail, among others. Alternatively, theresults may be posted on a web site or another medium (such as adatabase) for later retrieval by the user.

In another exemplary embodiment, acquisition device 200 may include aportion or all of the modules for carrying out different aspects of theinvention as summarized above and described in more detail herein below.In this exemplary embodiment, the images acquired by acquisition device200 may be analyzed on the device itself, thereby eliminating the needfor the images to be sent to separate computing device 130 connected toacquisition device 200 via network 245. Alternatively, a partialanalysis may be performed in acquisition device 200 and the images maystill be sent to separate computing device 130 for further analysis.

Light sources 120 that are on the top and at the bottom of acquisitiondevice 200 may be white light sources and light sources 120 on the sidesof acquisition device 200 may be UV light sources. The white lightsources can be conventional off-the-shelf flash light sources, such asflash light source 300 shown in FIG. 3A. Each of UV light sources 120can be one converted from light source 300 by changing low-pass filter310 in front of light source 300 into UV filter 310.

In one exemplary embodiment, as shown in FIGS. 3A-B, UV filter 310 is abandpass filter that provides transmission spectrum 320 having a widthof about 50 nm and a peak wavelength of about 365 nm. In comparison,low-pass filter 310 would provide a transmission spectrum, such as oneof spectra 330 shown in FIG. 3B, that drops sharply to near zero in theUV wavelength range and stays relatively flat in the visible wavelengthrange. In addition to the white-light and UV filters, some or all oflight sources 120 may also have infrared absorbing filters 315installed. Infrared absorbing filters 315 help to prevent heat fromlight sources 120 to be applied to subject 101 by filtering outwavelengths greater than, for example, 700 nm.

Acquisition device 200 may be installed in an imaging box, such as box410 shown in FIG. 4, which illustrates an exemplary setup of system 100.Imaging box 410 helps to prevent ambient light from entering sensor 212and interfering with the analysis of skin conditions. An example of suchan imaging box is the Facial Stage DM-3 commercially available fromMoritex Corporation, of Tokyo, Japan. FIG. 4 also shows acquisitiondevice 200 placed near a center in the back of box 410, light sources120 on top and sides of optical assembly 112, and a pedestal or chinrest 412 near opening 414 of imaging box 410 on which subject 101 canrest and stay still during imaging acquisition. FIG. 4 also shows, as anexample, computing device 130 and display 140 as parts of a laptopcomputer and printer 150 placed under the laptop computer.

In one exemplary embodiment of the present invention, as shown in FIG.5, computing device 130 can be any computing device having a centralprocessing unit (“CPU”) such as CPU 510, memory unit 520, at least onedata input port 530, at least one data output port 540, and userinterface 550, interconnected by one or more buses 560. Memory unit 520preferably stores operating system software 522 and other softwareprograms including program 524 for analyzing skin conditions usingdigital images. Memory unit 520 further includes data storage unit 526for storing image data transferred from acquisition device 200 throughone of the at least one data input port 530 and for storing prior skincondition results associated with subject 101 and other data or datastructures generated during current execution of program 524, asdiscussed below.

Program 524 may be organized into modules which include codedinstructions and when executed by CPU 510, cause computing device 130 tocarry out different aspects, modules, or steps of a method forautomatically identifying a person according to the present invention.All or part of memory unit 520, such as database 526, may reside in adifferent geographical location from that of CPU 510 and be coupled toCPU 510 through one or more computer networks.

Program 524 may also include a module including coded instructions,which, when executed by CPU 510, cause computing device 130 to providegraphical user interfaces (“GUI”) for a user to interact with computingdevice 130 and direct the flow of program 524. An example of a GUI forcapturing digital images of subject 101 is illustrated in FIG. 6 as GUI600.

Referring now to FIG. 7A, a flowchart illustrating method 700 foranalyzing skin conditions using digital images according to an exemplaryembodiment of the present invention is provided. As shown in FIG. 7A,method 700 includes module 710 for acquiring digital images of subject101. In one exemplary embodiment, the acquired digital images include afirst white-light image and a first UV image. Each of the firstwhite-light and UV images includes a plurality of pixels. Each pixel inthe first white-light or UV image corresponds to a pixel in sensor 114.

In one exemplary embodiment, each of the pixels in sensor 114 includesthree sub-pixels corresponding to three color channels for sensing threecolor components in a received light signal. Thus, each pixel in thewhite-light and UV image includes values associated with the three colorchannels, which are referred to sometimes in this document as pixelvalues. The pixel values may range, for example, between 0 and 255.

The images captured by sensor 114 and the images used by computingdevice 130 may be of different formats. An appropriate image conversionsoftware may be used by computing device 130 to convert an image format,such as BMP, TIFF, or FITS, used by acquisition device 200 to anotherimage format used by computing device 130. The images from acquisitiondevice 200, after any conversion, may be initially processed bycomputing device 130 using conventional techniques for dark currentand/or intensity correction, and image manipulation or enhancement,before being used for analyzing skin conditions.

The images may also be initially processed to have some pixels, such asthose at the four corners of a rectangular image, taken out because itmay be easy to tell that they have collected information fromsurrounding objects, instead of from subject 101. Thus, each of theacquired digital images, such as the first white-light and UV images, isreferred to as either the original image acquired by acquisition device200 or an image derived from the original image after one or more formator color space conversions, and/or after some initial processing such asthose stated above.

Generally, subject 101, or part of it, that is captured in the imagesinclude both skin and non-skin portions or features, such as hair,clothing, eyes, lips, nostrils, etc. Furthermore, some of the objectssurrounding subject 101 may also be captured in the images. Therefore,the pixels in the first white-light and UV images often include bothskin pixels, meaning pixels that have captured signals from the skinportions of subject 101, and non-skin pixels, meaning pixels that havecaptured signals from non-skin features of subject 101 or from objectssurrounding subject 101.

Since non-skin pixels may interfere with the analysis of skinconditions, method 700 further includes module 720 for identifying, on apixel by pixel basis, skin pixels and/or non-skin pixels in the firstwhite-light and/or UV image, and module 730 for obtaining resultsassociated with at least one skin condition using only information inthe skin pixels in the first white light and UV images.

Module 730 may include sub-modules 732 for performing UV damage and skintone analysis, and sub-modules 734 for locating and quantifyinglocalized skin conditions, such as one or more types of acne, pores,wrinkles, sun spots, different kinds of pigmentation including freckles,moles, growths, scars, acne, and fungi, growths, etc. Module 730 mayalso include sub-modules (not shown) for examining other skinconditions, such as skin tone, UV damage, hydration levels, collagencontent, skin type, topical inflammation or recent ablation, keratosis,deeper inflammation, erythema and/or any or the other skin conditionsidentifiable using the information in one or both of the white-light andUV images according to knowledge known to those familiar with the art.Module 730 may also include sub-modules for performing featuremeasurements such as the size and volume of a lip, nose, eyes, ears,chins, cheeks, forehead, eyebrows, among other features.

Method 700 further includes module 740 in which module 740 interactswith database 526 to store the current results in database 526, comparethe current results with prior results associated with the same subject101, and/or to classify the skin conditions based on the comparison.Method 700 further includes module 750 for outputting and/or displayingresults from the analysis. The results compared may include statisticalresults or other data analysis quantifying the skin conditions that areidentified and classified for the subject.

Prior to generating the current results, an alignment of the subject'sportion of a body surface being analyzed, such as the subject's face, isperformed as shown in FIG. 7B. The alignment ensures that imagesacquired for generating the current results are aligned with the imagesacquired for generating the previous results for the same subject. Agrid is used to align portions of the body surface of the subject beinganalyzed, such as the subject's nose, eyes, and mouth, with the sameportions displayed on previous images acquired for generating previousresults for the same subject.

For example, image 760 shows an image of the subject's face acquired forgenerating the previous results being displayed on a grid for moreaccurate placement of the face's features, such as the subject's eyes,nose, and mouth. Image 770 shows the same image on a grid overlying animage being acquired at a later time for generating current results forthe subject. The two images are aligned to guarantee that the resultsobtained at the two different times reflect the same positioning of facefeatures at the two times.

FIG. 8A illustrates process steps in module 710 for acquiring thedigital images of subject 101 according to one exemplary embodiment ofthe present invention. As shown in FIG. 8A, module 710 includes step 810in which the aspect ratio of sensor 114 is adjusted according todimensions of subject 101, and step 820 in which a light absorbing cloakis placed over subject 101 to cover as much as possible non-skinportions of subject 101.

For example, as illustrated in FIG. 8B, a person in front of imaging box410 to have his or her face imaged by acquisition device 200 may havehis or her shoulders and chest covered by cloak 880 such that theperson's clothing would not be captured by acquisition device 200 andthat the person is allowed to reach full fluorescence under UVillumination. In one exemplary embodiment, cloak 880 is made of one ormore layers of light absorbing fabric such as one known as Tuf-Flock orTough Lock, which is a vinyl backed velour that can be purchased atphotography specialty stores.

Module 710 further includes step 830 in which UV light sources 120 areturned on to send a flash of UV light to subject 101. The flash of UVlight should include a band of UV wavelengths that can cause the skinassociated with subject 101 to fluoresce, as illustrated in FIG. 3B. Atabout the same time, the shutter of acquisition device 200 camera isopened at step 840 so that the first UV image is captured by sensor 114.

The application of UV light to dermatology and health care has beenresearched and utilized in order to aid in the detection and diagnosisof a number of afflictions or skin disorders. Given that most livingorganisms fluoresce upon excitation through the absorption of light, aphenomenon known as auto-fluorescence, it has been shown that differentorganisms can be classified through their Stokes shift values. Stokesshift, as generally used herein, is the difference between peakwavelength or frequency of an absorption spectrum and peak wavelength orfrequency of an emission spectrum. Furthermore, UV light can penetratedeeper into the skin than visible light, making it possible to detectsubsurface skin conditions (i.e., skin conditions below the surface) andallowing for early diagnosis of melanoma and other skin cancer symptoms.

Therefore, by acquiring the first UV image, the embodiments of thepresent invention are able to combine the knowledge of auto-fluorescenceof the skin and image processing technologies to provide automateddetection and analysis of subsurface skin conditions, as described inmore detail below.

Module 710 further includes step 850 in which white-light sources 120are turned on to send a flash of white light to subject 101. The flashof white light preferably has wavelengths that span across a fullspectrum of visible light or a substantial portion of it. At about thesame time, the shutter of acquisition device 200 is opened at step 860so that the first white-light image is captured by sensor 114.

Module 710 further includes step 870 in which the first white-light andUV images are transferred from acquisition device 200 into computingdevice 130 using conventional means and stored in database 526 forsubsequent processing, and in which appropriate image conversion and/orinitial processing steps are performed as discussed above.

In module 720, skin pixels in the first white-light and UV images areidentified by examining each pixel in the first white-light and/or UVimage to determine if properties of the pixel satisfy predefinedcriteria for skin pixels, according to one embodiment of the presentinvention. The properties of a pixel may include the pixel values, thepixel's position in the image, pixel values of one or more correspondingpixels in one or more other images (as discussed below), and/or itsrelationship with a skin map or skin mask.

As shown in FIG. 9A, module 720 includes step 910 in which each pixel inthe first white-light image is examined to determine if the pixel valuesassociated therewith satisfy a first set of predefined criteria for skinpixels. The criteria for skin pixels may be different for differentcolor spaces, as illustrated in FIG. 9B, which lists, for each of aplurality of color spaces, ranges of values associated with differentcolor channels for likely skin pixels.

For example, assuming the first white-light image being in a first colorspace, such as the red-green-blue (“RGB”) color space, pixels that havethe red channel (channel 1) values in the range of 105-255, the greenchannel (channel 2) values in the range of 52-191, and the blue channel(channel 3) values in the range of 32-180 are likely to be skin pixels.Thus, as shown in FIG. 10( a), after examining the pixels in firstwhite-light image 1010, part of the pixels in first white-light image1010 are considered to be likely skin pixels, as illustrated by thewhite blocks in FIG. 10( a), and the rest of the pixels in firstwhite-light image 1010 are determined to be non-skin pixels, asillustrated by the black blocks in FIG. 10( a).

To be more accurate in identifying the skin pixels, module 720 furtherincludes step 920 in which first white-light image 1010 is converted toat least one other white-light image in at least one other color space,such as white-light image 1020 in a second color space illustrated inFIG. 10( b), and white-light image 1030 in a third color spaceillustrated in FIG. 10( c). Each pixel in the at least one otherwhite-light image corresponds to a respective pixel in the firstwhite-light image. The first, second, and third color spaces can bedifferent ones selected from commonly known color spaces, such as theRGB, YIQ, LAB, YcBcR, and HSV color spaces, and/or any proprietary colorspaces.

Module 720 further includes step 930 in which, for each of the at leastone other white-light images, the pixels corresponding to the likelyskin pixels in the first white-light image 1010 are further examinedagainst criteria for skin pixels associated with the respective colorspace. For example, in second white-light image 1020, all pixelscorresponding to non-skin pixels in first white-light image 1010 aredeemed to be non-skin pixels and are illustrated in FIG. 10( b) as blackblocks, and pixels corresponding to likely skin pixels in firstwhite-light image 1010 are further examined against criteria for skinpixels associated with the second color space. As a result, more pixelswould be determined as non-skin pixels, which are shown in FIG. 10( b)as blocks with stripes. The rest of the pixels in second white-lightimage 1020 are considered to be likely skin pixels and are illustratedby the white blocks in FIG. 10( b).

Furthermore, in third white-light image 1030, all pixels correspondingto non-skin pixels in second white-light image 1020 are deemed to benon-skin pixels and are illustrated in FIG. 10( c) as black blocks andblocks with stripes, and pixels corresponding to likely skin pixels insecond white-light image 1020 are further examined against criteria forskin pixels associated with the third color space. As a result, morepixels would be determined as non-skin pixels, which are shown in FIG.10( c) as blocks with dots. The rest of the pixels in third white-lightimage 1020 are considered to be likely skin pixels and are illustratedby the white blocks in FIG. 10( c). This process may continue until alast one of the at least one other white-light image (the lastwhite-light image) is examined.

To be even more accurate in identifying the skin pixels and to make surethat non-skin pixels are not considered in analyzing the skinconditions, module 720 may include further step 940 in which coordinatereference 1040, such as the one shown in FIG. 10( d), is used toclassify more of the likely skin pixels as non-skin pixels. Coordinatereference 1040 may be pre-stored template together with a plurality ofother coordinate reference or templates in database 526 in memory unit520 of computing device 130, and selected as being a suitable one forsubject 101.

Coordinate reference 1040 defines certain pixels in any of thewhite-light images as non-skin pixels (shown as black blocks in FIG. 10(d)) based on their coordinates or positions in the image. So if any ofthe likely skin pixels in the last white-light image have coordinatesthat are defined as coordinates for non-skin features in coordinatereference 1040, these pixels are determined to be non-skin pixels. Therest of the like skin pixels in the last white-light image are finallyidentified as skin pixels, and all of the pixels in each of the otherwhite-light images or the UV image that correspond to the skin pixels inthe last white-light image are also identified as skin pixels. The restof the pixels in each of the white-light or UV images are considered asnon-skin pixels.

To help identify skin pixels in all of the images of subject 101 duringsubsequent processing, module 720 may include further step 950 in whicha skin map or skin mask is generated. In one embodiment of the presentinvention, as shown in FIG. 10( e), skin map 1050 includes a matrix ordata group having a plurality of elements, each corresponding to a pixelin any of the white-light or UV images of subject 101. Those matrixelements corresponding to skin pixels in the last white-light image(shown as white blocks in FIG. 10( e)) are defined as skin elements, andeach is assigned a first value.

In contrast, those matrix elements corresponding to non-skin pixels inthe last white-light image (shown as black blocks in FIG. 10( e)) aredefined as non-skin elements, and each is assigned a second value thatis distinct from the first value. In one exemplary embodiment, the firstvalue is a large number, such as 255, and the second value is a smallnumber, such as 0. Thus, whether a pixel in any of the white-light andUV images is a skin pixel can be easily determined by looking up thevalue contained in the corresponding element in skin map 1050, and thiscan be done in step 960.

In one exemplary embodiment of the present invention, module 730includes sub-module 1100 for obtaining UV damage results using the skinpixels in at least the first UV image, as illustrated in FIG. 11.Sub-module 1100 includes step 1110 in which the first UV image, if it isnot in the RGB color space, is converted into the RGB color space, step1120 in which an average is computed from all of the green channelvalues in the skin pixels of the first UV image, and step 1130 in whicha first standard deviation is computed from the green channel values inthe skin pixels. The first standard deviation value can be used toindicate quantitatively the amount of UV damage in the skin of subject101.

Alternatively or additionally, sub-module 1100 may include a furtherstep 1140 in which a second standard deviation is computed from thegreen channel values in the skin pixels of one of the white-lightimages, and an average of the first and second standard deviation valuescan be used to indicate quantitatively the amount of UV damage in theskin of subject 101.

In order to visually display the UV damage results in an enhanced view,a UV damage enhanced white-light image is formed in step 1150 that has aplurality of pixels each corresponding to a respective pixel in thefirst white-light image. Thus, a non-skin pixel in the first white-lightimage corresponds to a non-skin pixel in the UV damage enhancedwhite-light image. In one exemplary embodiment, the non-skin pixels inthe UV damage enhanced white-light image have the same pixel values asthe pixel values in the non-skin pixels in the first white-light image.

For each skin-pixel in the UV damage enhanced white-light image, the redchannel and blue channel values therein are the same as those in thecorresponding skin pixel in the first white-light image. The greenchannel value therein is derived from both the green channel value inthe corresponding skin pixel in the first white-light image and thegreen channel value in the corresponding pixel in the first or second UVimage.

For example, assuming GEN is the green channel value in a skin pixel inthe UV damage enhanced white-light image, and GWL and GUV are the greenchannel value in the corresponding skin pixels in the first white-lightand the first (or second) UV images, respectively, GEN may be assignedto be an average of GWL and GUV, that is:GEN=½(GWL+GUV)  (1)

Other ways of enhancing the UV damage results are also possible, forexample:GEN=GWL+(GUV−GAVG)  (2)where GAVG is the average green channel value computed in step 1120.

In one exemplary embodiment of the present invention, module 730includes sub-module 1200 for obtaining skin tone results using the skinpixels in any of the white-light images, as illustrated in FIG. 12.Sub-module 1200 includes step 1210 in which an average is computed fromvalues associated with each of the three color channels in the skinpixels of the white-light image, step 1220 in which a standard deviationis computed for each of the color channels in the skin pixels, and step1230 in which an average of the standard deviation values computed instep 1220 is obtained as a measure of the skin tone of subject 101.

In one exemplary embodiment of the present invention, module 730includes sub-module 1300 for obtaining results related to certain skinconditions, as illustrated in FIG. 13A. Sub-module 1300 includes step1310 in which color and intensity values are computed from the pixelvalues associated with each pixel in one of the UV images, and step 1320in which the color and intensity values for each pixel are examined withreference to at least one look-up table to determine if the pixelsatisfies criteria for any of a list of skin conditions in the look-uptable. The at least one look-up table may include those compiled usingknowledge known in the art, or through proprietary research and/orempirical studies.

For each skin pixel identified to be associated with a certain skincondition, the surrounding pixels are also examined to determine thesize and shape of a skin area having the skin condition. In the case ofmelanoma, the shape and size of an affected skin area can be used tohelp determine the type and amount of skin cancer damage.

FIG. 13B illustrates an exemplary look-up table for pores and sluggishoil flow that may be included in the at least one look-up table. Forexample, if a first skin pixel has a white color and an intensity valueexceeds 130, the skin pixel is likely one of a group of contiguouspixels that have captured fluorescence coming from an inflamed pore uponillumination by a UV flash. To confirm, surrounding skin pixels are alsoexamined to see if some of them are also white in color and haveintensity values over 130. If none or few of the pixels satisfy thiscriteria, the first skin pixel is not associated with an inflamed pore.Otherwise, an inflamed pore is identified, and in step 1330, the numberof skin pixels associated with the inflamed pore is determined as ameasure for the shape and size of the pore, and an average of theintensity value associated with the number of skin pixels is computed asa quantitative indication of the severity of the pore.

It should be understood by one of ordinary skill in the art that FIG.13B only illustrates some examples of the criteria that can be used bymodule 1300. Alternatively or additionally, module 1300 may use otherlook-up tables associated with other skin conditions, such as thoseknown in the art. As described hereinabove, skin conditions that may beanalyzed by the methods and systems of the present invention mayinclude, but are not limited to, skin tone, UV damage, pores, wrinkles,hydration levels, collagen content, skin type, topical inflammation orrecent ablation, keratosis, deeper inflammation, sun spots, differentkinds of pigmentation including freckles, moles, growths, scars, acne,fungi, erythema and other artifacts. Information in the skin pixels mayalso be used to perform feature measurements such as the size and volumeof a lip, nose, eyes, ears, chins, cheeks, forehead, eyebrows, amongother features.

Sub-module 1300 further includes step 1340 in which statistical resultssuch as a total number of all types skin conditions, and/or a totalnumber of each of a plurality of skin conditions are computed.

In one exemplary embodiment of the present invention, module 730 furtherincludes sub-module 1400 for evaluating wrinkles on subject 101, asshown in FIG. 14. Sub-module 1400 includes step 1410 in which aconventional or proprietary edge detector, such as the publiclyavailable Canny edge detector, is used to detect edges in any of thewhite-light image after the non-skin pixels are extracted from thewhite-light image, and step 1420 in which each detected edge is examinedto determine if it is a wrinkle.

In one exemplary embodiment, an edge is determined to be a wrinkle if apredetermined percentage of corresponding pixels have pixel value thatsatisfy predetermined criteria. In one exemplary embodiment, thepredetermined criteria may be derived from pre-stored or recentlycomputed skin color values for subject 101. For example, average valuesfor the red, green, and blue color channels for subject 101 can be usedto set the criteria, and if a predetermined percentage, such as over 70%of the pixels corresponding to the edge have their red, green, and bluechannel values roughly proportional to the average red, green bluechannel values, the edge would be determined as a wrinkle.

Sub-module 1400 may further include step 1430 in which the pixels aroundthe edges are examined to determine the degree of the wrinkle. Forexample, for a fine line wrinkle, the pixels corresponding to the edgeindicating the likely presence of the wrinkle should have intensityvalues substantially less than those of the surrounding pixels, and fora deep wrinkle, a wider edge should be expected, and there should be awider line of pixels having depressed intensity values.

Sub-module 1400 may further include step 1440 in which the number of allwrinkles or wrinkles of a certain degree is counted, and a distributionof the wrinkles across the subject may also be computed.

In one exemplary embodiment, the module for outputting/displaying theresults of skin analysis includes sub-module 1500 for displaying theresults with a GUI. As shown in FIG. 15A, sub-module 1500 includes step1510 in which a user input selecting a skin condition for display isreceived through the GUI, step 1520 in which an image having theselected skin condition highlighted or enhanced is displayed, and step1530 in which computation results quantifying the skin condition isdisplayed.

For example, assuming that the user has selected pores or a type ofpores as the skin conditions for display, the GUI according tosub-module 1500 may display a color image of the subject with all poresor the selected type of pores highlighted as, for example, bright whitedots on the color image. Different pores may also be highlighted usingdifferent colors. At the same time or on the same screen, a pore countfor all of the pores found, and/or for each of different types of poresmay be listed.

As shown in FIG. 15B, sub-module 1500 may also display the skin analysisresults in a timeline showing changes of selected skin analysis resultsover time for the same subject 101. As shown in FIG. 15C, sub-module1500 may also display selected skin analysis results as compared withprevious results related to the same skin condition for the same subject101. The results compared may include statistical results or other dataanalysis quantifying the skin conditions that are identified andclassified for the subject.

The foregoing descriptions of specific embodiments and best mode of thepresent invention have been presented for purposes of illustration anddescription only. They are not intended to be exhaustive or to limit theinvention to the precise forms disclosed. Specific features of theinvention are shown in some drawings and not in others, for purposes ofconvenience only, and any feature may be combined with other features inaccordance with the invention. Steps of the described processes may bereordered or combined, and other steps may be included. The embodimentswere chosen and described in order to best explain the principles of theinvention and its practical application, to thereby enable othersskilled in the art to best utilize the invention and various embodimentswith various modifications as are suited to, the particular usecontemplated. Further variations of the invention will be apparent toone skilled in the art in light of this disclosure and such variationsare intended to fall within the scope of the appended claims and theirequivalents. The publications referenced above are incorporated hereinby reference in their entireties.

What is claimed is:
 1. A system for analyzing physical conditionsassociated with a subject, comprising: an image acquisition deviceincluding: at least one UV light source for illuminating the subject; atleast one white light source for illuminating the subject; an opticalassembly comprising a lens; and a frusto-conical source light shieldextending outwardly from the lens of the optical assembly; wherein saidat least one white light source has a ring-shaped configuration and ispositioned behind the source light shield, said device configured toacquire a first white-light image and a first UV image of a physicalfeature of the subject, each of the first white-light and UV imageshaving a plurality of pixels, each pixel in the first UV imagecorresponding to a respective pixel in the first white-light image; acomputer system configured to identify, on a pixel by pixel basis,feature pixels in the first white-light and UV images, and to obtainresults associated with at least one physical condition usinginformation in the feature pixels in the first white light and UVimages, wherein at least one of said UV and white light sourcescomprises at least one LED light source.
 2. The system of claim 1,wherein the image acquisition device has a sensor that can be rotated toadjust an aspect ratio of the white-light or UV image according controlsignals from the computer system.
 3. The system of claim 1, wherein theimage acquisition device further comprises a sensor, wherein the opticalassembly is configured to form images of the subject on the sensor. 4.The system of claim 1, wherein said image acquisition device comprises aplurality of LED light sources disposed about the lens of the opticalassembly.
 5. The system of claim 4, wherein the plurality of LED lightsources are disposed concentrically about the lens of the opticalassembly.
 6. The system of claim 1, wherein said light sources includeat least one white LED light source and at least one UV LED lightsource.
 7. The system of claim 1, wherein said light sources include atleast one light source having an infrared absorption filter installedthereon.
 8. The system of claim 1, wherein said at least one UV LED hasan emission wavelength ranging from about 348 nm to about 375 nm.
 9. Thesystem of claim 8, wherein said at least one UV LED has an emissionwavelength of about 365 nm.
 10. The system of claim 1, wherein saidoptical assembly further comprises a zoom lens.
 11. The system of claim10, wherein said optical assembly further comprises a zoom lens controlsystem.
 12. The system of claim 1, wherein said optical assembly furthercomprises a broadband circular polarizer.
 13. The system of claim 1,wherein said light sources include a plurality of LED light sources. 14.The system of claim 13, wherein said LED light sources are disposedsymmetrically on a ring concentrically disposed about the lens of theoptical assembly.
 15. The system of claim 1, wherein said light sourcesinclude at least three LED light sources.
 16. The system of claim 1,wherein said light sources include at least eight LED light sources. 17.The system of claim 1, wherein said at least one white light sourcecomprises at least two LED light sources of distinct emissionwavelengths in the visible spectrum.
 18. The system of claim 1, whereinsaid at least one UV light source comprises at least two LED lightsources of distinct emission wavelengths in the UV spectrum.
 19. Thesystem of claim 1, wherein said at least one UV light source is an LEDlight source.
 20. The system of claim 1, wherein said at least one whitelight source is an LED light source.
 21. The system of claim 1, whereinthe source light shield is formed of a light diffusing material.
 22. Thesystem of claim 1, wherein the image acquisition device furthercomprises a chin rest.
 23. The system of claim 1, wherein the imageacquisition device further comprises a forehead rest.
 24. The system ofclaim 1, wherein the image acquisition device further comprises anambient light shield positioned at least partially over the distal endof the frusto-conical source light shield.
 25. The system of claim 24,wherein the ambient light shield is formed of an opaque material. 26.The system of claim 24, wherein the ambient light shield has areflective interior surface.
 27. The system of claim 1, wherein theimage acquisition device further comprises a housing having a chambersized and configured to enclose the white light source.
 28. A system foranalyzing physical conditions associated with a subject, comprising: animage acquisition device including: at least one UV light source forilluminating the subject; at least one white light source forilluminating the subject; an optical assembly comprising a lens; afrusto-conical source light shield extending outwardly from the lens ofthe optical assembly; and an ambient light shield positioned at leastpartially over the distal end of the frusto-conical source light shield;said device configured to acquire a first white-light image and a firstUV image of a physical feature of the subject, each of the firstwhite-light and UV images having a plurality of pixels, each pixel inthe first UV image corresponding to a respective pixel in the firstwhite-light image; a computer system configured to identify, on a pixelby pixel basis, feature pixels in the first white-light and UV images,and to obtain results associated with at least one physical conditionusing information in the feature pixels in the first white light and UVimages, wherein at least one of said UV and white light sourcescomprises at least one LED light source.